The Perseae mite, Oligonychus perseae Tuttle, Baker & Ababatiello (Acari: Tetranychidae), constitutes a significant threat to avocado crops in the Canary Islands, often resulting in substantial economic losses for growers. Despite efforts to control this pest through the release of phytoseiid predators, particularly Neoseiulus californicus (McGregor), satisfactory control has not been achieved. The prevalence of the phytoseiid species Euseius stipulatus (Athias-Henriot) in avocado orchards suggests its potential as a biological control agent for managing O. perseae populations. This study evaluated the impact of diet, specifically Carpobrotus edulis pollen and O. perseae eggs, on the life cycle of E. stipulatus. The predator exhibited a notable preference for consuming eggs during its developmental stages. A type II functional response was observed in the predator, where the number of eggs consumed increased proportionally with the quantity offered. While E. stipulatus demonstrated the ability to sustain itself and reproduce by preying on O. perseae eggs, certain parameters such as longevity, fecundity, and oviposition time were significantly enhanced by pollen.

First report of three obligatory thrips predators in the Canary Islands

The white mango scale, Aulacaspis tubercularis Newstead (Hemiptera: Diaspididae) is an exotic pest that causes important economic damage in the Spanish mango crops. Prospecting for potential natural enemies, the parasitic wasp Arrhenophagus chionaspidis Aurivillius (Hymenoptera: Encyrtidae) was first detected attacking immature male stages of A. tubercularis in Tenerife (Canary Islands, Spain) in 2022. Still, its influence on pest populations was not evaluated. This endoparasitoid was identified by its morphological characteristics and characterized for the first time by DNA barcoding of adult females using partial (651 bp) mitochondrial cytochrome oxidase 1 (mtCOI) gene (Genbank accession number OQ646824). Its potential utilization as biological control agent of A. tubercularis in mango crops is discussed. Therefore, further studies need to be conducted about its biology, population dynamics and rate of natural parasitism for the development of effective biological control strategies of A. tubercularis in mango.

Trioza erytreae (Del Guercio, 1918) (Hemiptera: Triozidae) is a citrus pest which produces gall symptoms on leaves and transmits bacteria associated with the citrus disease Huanglongbing, ‘Candidatus Liberibacter’ spp. In the present work, the biology and behaviour of T. erytreae were studied in different rootstock–cultivar combinations. Six rootstocks were used, Flying dragon (FD), ‘Cleopatra’ mandarin (CL), Carrizo citrange (CC), Forner-Alcaide no.5 (FA5), Forner-Alcaide no.517 (FA517) and Citrus macrophylla (CM), and six scion cultivars: ‘Star Ruby’, ‘Clemenules’, ‘Navelina’, ‘Valencia Late’, ‘Fino 49’ and ‘Ortanique’. Survival and oviposition were evaluated in a no-choice trial, and preference in a choice trial, all of them under greenhouse conditions. Trioza erytreae did not show a clear settle preference for any citrus combination. However, it was able to lay more eggs in ‘Fino 49’ grafted on CC than on FD. In terms of survival, ‘Ortanique’ grafted onto FA5 was more suitable than when grafted onto FA517, and in the case of ‘Valencia Late’, when it was grafted onto CM rather than CC. Our results showed that T. erytreae behave differently depending on the citrus combination.

The chilli thrips Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) is an invasive polyphagous pest of several crops, and is native to South and East Asia. In recent decades, this thrips has successfully established in parts of the African and American continents. In the EPPO region its distribution is limited to Israel and Türkiye, and it is considered as under eradication in mainland Spain. This paper presents the first report of S. dorsalis on the island of Tenerife (Canary Islands, Spain), where individuals were initially found infesting mango in 2016, and subsequent inspections revealed infestations in 2022 that allowed its identification.

Avocado production has boomed worldwide in recent years, and Spain, including the Canary Islands, has been no exception. The number of avocado growers in the region has increased significantly as growers recognize the potential of this crop. However, several species of spider mites (Tetranychidae) pose a risk to this crop, with the genus Oligonychus being the most diverse and having the greatest economic impact. In particular, Oligonychus perseae (Tuttle, Baker and Abbatiello) has been reported as the one mainly responsible for the economic damage in major avocado-producing regions worldwide. In this paper, we aim to present an overview of the studies conducted and the measures implemented to mitigate the impact of O. perseae after its arrival in the Canary Islands. Our objective is to provide a detailed description of the current status of this pest (O. perseae), with special attention to its situation 17 years after its first appearance in avocado crops in the Canary Islands. In doing so, we aim to provide valuable insights and knowledge to understand and manage better the challenges posed by O. perseae in this region.

The psyllid fauna of the Canary Islands is reviewed on the basis of recent field work on Tenerife, La Gomera, La Palma Gran Canaria and Lanzarote, as well as the examination of material deposited in several collections. Two new genera and 16 new species are described: Drepanoza Bastin, Burckhardt & Ouvrard gen. nov., Percyella Bastin, Burckhardt & Ouvrard gen. nov., Agonoscena atlantica Bastin, Burckhardt & Ouvrard sp. nov., A. sinuata Bastin, Burckhardt & Ouvrard sp. nov., Arytaina meridionalis Bastin, Burckhardt & Ouvrard sp. nov., Cacopsylla crenulatae Bastin, Burckhardt & Ouvrard sp. nov., C. falcicauda Bastin, Burckhardt & Ouvrard sp. nov., Diaphorina gonzalezi Bastin, Burckhardt & Ouvrard sp. nov., Drepanoza canariensis Bastin, Burckhardt & Ouvrard sp. nov., D. fruticulosi Bastin, Burckhardt & Ouvrard sp. nov., D. molinai Bastin, Burckhardt & Ouvrard sp. nov., Euphyllura confusa Bastin, Burckhardt & Ouvrard sp. nov., Percyella benahorita Bastin, Burckhardt & Ouvrard sp. nov., P. canari Bastin, Burckhardt & Ouvrard sp. nov., P. gomerita Bastin, Burckhardt & Ouvrard sp. nov., P. guanche Bastin, Burckhardt & Ouvrard sp. nov., Strophingia canariensis Bastin, Burckhardt & Ouvrard sp. nov. and S. paligera Bastin, Burckhardt & Ouvrard sp. nov. Arytaina insularis Loginova, 1976, stat. nov. is elevated from a subspecies of A. devia Loginova, 1976 to species rank. Five new combinations are proposed: Drepanoza fernandesi (Aguiar, 2001) comb. nov., D. lienhardi (Burckhardt, 1981) comb. nov., D. montanetana (Aguiar, 2001) comb. nov., D. pittospori (Aguiar, 2001) comb. nov. and Lauritrioza laurisilvae (Hodkinson, 1990) comb. nov., all transferred from Trioza. The hitherto unknown last-instar immatures are described for Megadicrania tecticeps Loginova, 1976, Cacopsylla atlantica (Loginova, 1976) and Lauritrioza laurisilvae (Hodkinson, 1990). We also report Agonoscena targionii (Lichtenstein, 1874) for the first time from the Canary Islands. Our review increases the number of known psyllid taxa from the Canary Islands to 24 genera and 62 species (one of which remains undescribed). Endemism, host plant relationships and biogeographic patterns are discussed. Keys for the identification of adults and immatures are provided, as well as information on host plants, distribution and predators.

Tecia solanivora (Povolný 1973), is a quarantine pest in Europe. Identified in Guatemala in the 1970s, it spread throughout Central and South America, reaching the Canary Islands in 1999 and mainland Spain in 2015. The pest has caused prohibitive economic losses both in the field and in storage, where losses can reach 100%. In the absence of approved chemical treatments, the use of an egg predatory mite, Blattisocius tarsalis (Berlese 1918), and the egg parasitoid, Trichogramma euproctidis (Girault 1911), is being studied for use in storage. Previous laboratory studies have confirmed their potential for use in non-refrigerated stores, typically between 15 and 20 °C. In the present work, we compared the efficacy of both natural enemies under semi-storage conditions. We observed that while both T. euproctidis and B. tarsalis reduced the T. solanivora populations (with an efficacy of 82.95 ± 7.32% and 49.06 ± 2.69%, respectively) and the number of mites per tuber, only B. tarsalis resulted in undamaged tubers (65%). For this reason, the mite was selected and tested in storage conditions, obtaining promising results in the protection of infested tubers, suggesting potential for further investigation, adaptation and standardization of its use in real conditions.

The genus Dirphys Howard 1914 syn. n. is synonymized with Encarsia Förster, and treated as a species-group of Encarsia, referred to henceforth as the Encarsia mexicana species-group. The monophyly of Encarsia is discussed in relation to Dirphys. The new synonymy is based on phylogenetic analyses of the nuclear ribosomal 28S-D2 gene region (43 taxa, 510 bp). The Encarsia mexicana species-group is recovered as strongly monophyletic within Encarsia. All species of the Encarsia mexicana species-group are revised. The group includes six previously described species, and fourteen newly described species. All species are described (or redescribed) and illustrated. Detailed distributional data, and, where available, plant associate and host records are provided for all species. Encarsia myartsevae Kresslein and Polaszek nom. nov. is here proposed as a replacement name for Encarsia mexicana Myartseva, now preoccupied by Encarsia mexicana (Howard). A dichotomous identification key, supplemented by an online multiple-entry key, is provided for all species.

The Persea mite, Oligonychus perseae Tuttle, Baker & Abbatiello (Acari: Tetranychidae), is an economically important foliar pest of avocados in Spain. The effects of this mite on the foliar damage, production losses and economic impact were assessed in two avocado, cv. Hass, orchards located in the main growing areas of Spain (Northern Tenerife and Málaga) for 3 and 5 consecutive years, respectively. The economic injury level (EIL) for the optimization of the use of acaricides to control this mite was also established, considering three spraying strategies: (i) mite-free treatment (<50 mites per leaf), (ii) conventional treatment (50–150 mites per leaf), and (iii) control treatment (the absence of spraying). Persea mite populations were sampled fortnightly and foliar damage was estimated. At the end of each season, fruits were harvested, weighed and production losses were quantified. The cumulate mite-days (CMDs) had a significant effect on the percentage of leaf area damaged (PLAD) and yield reduction. High numbers of the Persea mite caused extensive damage to leaves, so a loss in tree yield was evident. However, for the middle population level, there was no evidence of yield losses. The quantitative EIL was estimated at a PLAD of 17%, equivalent to a CMDs of 178 mites per leaf, which is the amount of damage that should not be exceeded. In Northern Tenerife, with a mild climate, the Persea mite can reach significant populations that are maintained throughout the months. In avocado orchards in Málaga, the summer is hotter and drier, so the presence of the mite exists for a shorter duration in the seasons, with less damage to the leaves. In Tenerife, yield loss can be compensated by chemical treatments that permit pest control.

Spain is the number one citrus-producing country in the European Union and the sixth worldwide, with more than six million tons of citrus produced annually. Seven biorational insecticides (paraffin oil, azadirachtin, kaolin, garlic extract, orange oil, potassium soap and diatomaceous earth) recommended for control of different pests in organic citrus orchards were evaluated against Trioza erytreae (Del Guercio) in semi-field and field trials. All products affected T. erytreae survival in both types of trials. In the semi-field trial, diatomaceous earth resulted in the highest percentage mortality of T. erytreae nymphs, followed by kaolin, apart from on the final day of assessment when the highest mortality was recorded for paraffin oil, though this effect was not significantly different to that of the other insecticides. In the 2018 field trial, orange oil treatment resulted in the highest mortality rate of T. erytreae nymphs, followed by azadirachtin and garlic extract. This work provides citrus growers with useful information on the effects of several biorational insecticides on T. erytreae under field and semi-field conditions. Overall, the optimal T. erytreae nymph mortality was achieved with diatomaceous earth and orange oil under semi-field and field conditions, respectively.

Thrips of the subtropical genus Scirtothrips are emerging as important pests in several crops. Scirtothrips dorsalis has been increasingly invading new areas outside of its native region of South and East Asia causing economic damage to several crops. Scirtothrips inermis is another polyphagous species with worldwide distribution. Both species are polyphagous, and in recent years have emerged as key pests in strawberry. In this study, we first evaluated the predation and oviposition rate of commercially available phytoseiid predatory mites Amblyseius swirskii, Amblydromalus limonicus, Transeius montdorensis, and Neoseiulus cucumeris on larval stages of both Scirtothrips species, and oviposition rates of predatory mites on the supplementary food source Artemia franciscana cysts were also assessed. Predatory mites equally accepted both thrips species as prey and showed stable oviposition rates on these diets. Amblyseius swirskii and A. limonicus were the most voracious, also exhibiting the highest oviposition rate of the predators tested. We further evaluated the biological control potential of predatory mites and anthocorid predators Orius laevigatus and Orius limbatus in a greenhouse experiment. Predators were released preventively and supported with Artemia cysts before the introduction of S. inermis . Both Orius predators achieved good control of the pest, with O. limbatus developing higher numbers than O. laevigatus . Regarding phytoseiids, A. swirskii and A. limonicus both controlled the pest and built higher populations than T. montdorensis and N. cucumeris . Our results show that a preventive strategy based on phytoseiid or anthocorid predators in strawberry can be effective in suppressing S. inermis .

The Guatemalan potato moth (Tecia solanivora) is designated a quarantine pest by the European Union, causing severe production losses in potato crops. No effective chemical control alternatives are currently available, and cultural techniques are unable to reduce harvest losses to acceptable levels. With a focus on biological control, two egg parasitoids (Trichogramma euproctidis and Trichogramma achaeae) were selected and evaluated for use under field and storage conditions. Laboratory assays (choice and no-choice) indicated the preference of both parasitoids for T. solanivora vs. Phthorimaea operculella. Trichogramma euproctidis showed the highest parasitic activity for both moths. Analysis of functional response (at 15, 20, 25 and 27 °C) confirmed the high parasitic potential of T. euproctidis. Furthermore, in assays conducted under darkness conditions, T. achaeae was unable to parasitize eggs. However, in semi-field assays, T. achaeae was more efficient in searching for eggs in the soil than T. euproctidis. Based on these results, T. achaeae was selected to be tested under field conditions, and T. euproctidis was selected for testing under storage conditions.

Trioza erytreae (Del Guercio) (Hemiptera: Triozidae) is one of the vectors of the citrus greening or huanglongbing (HLB) disease, the most devastating citrus disease globally. A classical biological control program has been established to control this vector in Europe, where it has been threatening the citrus industry since its detection in mainland Spain and Portugal. For this, its main parasitoid Tamarixia dryi (Waterson) (Hymenoptera: Eulophidae) has been introduced. Here, we evaluated the nutritional value of T. erytreae honeydew as a suitable food source for T. dryi. This solid honeydew is the most abundant food source for the parasitoid in the field. Our results demonstrated that T. erytreae honeydew enhanced the longevity of T. dryi compared to other diets such as water, 'sucrose alone' or 'sucrose + protein'. Females fed on honeydew also oviposited more eggs than those fed on water or 'sucrose alone'. Finally, T. dryi fed on honeydew tended to parasitize more psyllids than those fed on the other diets. Chemical analyses demonstrated that T. erytreae honeydew contains proteins, and this can explain the increase in egg load of honeydew fed parasitoids. Further research is necessary to understand why these females tended to parasitize more than females fed on 'sucrose + protein'. Overall, these results contribute to understanding the successful and rapid establishment of T. dryi in Europe and to the successful rearing and release programs in newly invaded areas.

The Mediterranean Basin is the second largest citrus-producing region in the world and Spain is the highest producer of this region. Huanglongbing (HLB) is the most important and devastating citrus disease worldwide, the causal agents of which are three bacteria species that belong to the genus Candidatus Liberibacter. The main transmission of these pathogens is by two psyllid vectors, Diaphorina citri and Trioza erytreae. T. erytreae is a specific pest of plants from the Rutaceae family, which includes cultivated citrus. This insect has recently been detected in Mediterranean Basin countries, specifically in Spain and Portugal. The potential risk of HLB emergence has increased concern in the Spanish and Portuguese citrus growing areas, which require the performance evaluation of T. erytreae on conventional citrus rootstocks as a method for reducing the insect population. The aim of this work was to study the survival, development, oviposition and feeding preference of T. erytreae in non-grafted conventional citrus rootstocks. This study evaluates the preference of T. erytreae in potted plants of different conventional citrus rootstocks. Thus, six different non-grafted citrus rootstocks were used for these experiments: (a) Carrizo citrange; (b) Citrus macrophylla; (c) ‘Cleopatra’ mandarin; (d) Forner-Alcaide No. 5; (e) Forner-Alcaide No. 517, and (f) Poncirus trifoliata (‘Flying Dragon’). The behavior and survival of this psyllid was evaluated through the feeding preference of T. erytreae adults for different rootstocks and oviposition and survival of T. erytreae adults on the different citrus material. T. erytreae showed a clear preference for hosting and feeding on C. macrophylla, while Carrizo citrange was the most suitable rootstock for insect reproduction and survival followed by C. macrophylla. Conversely, P. trifoliata was the least attractive rootstock to T. erytreae adults and led to significantly lower T. erytreae survival. Our results suggest that conventional citrus rootstocks, such as Carrizo citrange and C. macrophylla, could increase T. erytreae populations.

The golden twin-spot moth (Chrysodeixis chalcites) is one of the most important pests in banana production on the Canary Islands (Spain). The efficacy of different biorational insecticides based on bioenzyme complexes (Intruder®), plant extracts: Rutaceae and Piperaceae (Avenger®), Rutaceae and Lauraceae (BioKnock®), cinnamon, citronella, and Menta (Cinamite®), Alliaceae and Solanacea (Garlitrol-Forte®), citrus (Prevam®), and neem oil (Indasol®) was assessed against C. chalcites. Laboratory assays included: choice (repellent effect), no choice, and contact toxicity on C. chalcites 2nd instar larvae. The highest repellent effect was observed with Prevam® (85.19 ± 1.7%), followed by Garlitrol® (68.44 ± 5.7%) and Intruder® (67.54 ± 4.3%). In no choice assays, Prevam® (0.92 ± 0.4%), Indasol® (0.98 ± 0.33%), and Intruder® (2.7 ± 0.33%) had the lowest leaf consumption. The contact toxicity assays showed the highest mortality with Intruder® both at 1 day and 7 days post-application (20.22 ± 2.98% and 77.77 ± 5.7%, respectively). In the screenhouse trial, the best results for C. chalcites larvae mortality, fruit damage, and fruit classification in quality categories 7 days after application of the bioinsecticide were obtained with Intruder®, Prevam®, and Indasol®. An economic analysis of biorational treatments was also performed. The results of this study provide successful alternatives to chemical pesticides for the control of C. chalcites on banana plants in the Canary Islands.

The recent spread of the African citrus psyllid, Trioza erytreae, one of the vectors of the devastating citrus disease, Huanglongbing (HLB), to parts of mainland Europe has created considerable concern. In this study, we show the efficacy of several insecticides with varying modes of action on different developmental stages of T. erytreae. In laboratory trials, spinetoram caused the highest mortality in T. erytreae eggs (between 80 and 90%), while dimethoate, lambda cyhalothrin, spinetoram, cyantraniliprole, and paraffin oil showed over 90% mortality on nymphs. Dimethoate, spinetoram and paraffin oil also demonstrated high efficacy against adults. In winter field conditions, dimethoate showed the best results to control T. erytreae nymph populations, and lambda cyhalothrin showed persistent egg control. Our results support the use of different insecticides to control T. erytreae for adults in winter, and for egg and nymph populations in spring and summer.

Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) is a significant pest in banana plantations in the Canary Islands. Field surveys were carried out to identify its naturally occurring parasitoids and estimate their parasitism rates between September 2007 and October 2010. Ch. chalcites was parasitized by six different larval/pupal parasitoid species: Cotesia sp., C. glomerata L. (Hym.: Braconidae), Aplomyia confinis Fallén (Dip.: Tachinidae), Hyposoter rufiventris Perez, Ctenochares bicolorus L. (Hym.: Ichneumonidae) and Aleiodes sp. (Hym.: Braconidae). Among them, Cotesia sp. was the most frequent species, accounting for 8.18% of parasitized larvae. High levels of egg parasitism were detected, with Trichogramma achaeae Nagaraja and Nagarkatti (Hym.: Trichogrammatidae) being the most widely distributed egg parasitoid. A greenhouse assay was also carried out on a commercial banana crop with the aim of evaluating the potential of T. achaeae as a biological control agent and compared with a chemical control. Five periodic inundative releases of 35 adults/m2 every 21 days were necessary to achieve an adequate parasitism level (56.25 ± 1.61%). Moreover, there was 15.75% less foliar damage in the biological control plot compared to the chemical control plot. These results indicate that T. achaeae could be a promising biocontrol agent of Ch. chalcites in greenhouse banana crops.

Tecia solanivora is the most prevalent pest causing damage to potato crops in fields in the Canary Islands, but even more so in the postharvest storage period. However, currently, there are no authorised chemical insecticides for potato storage facilities. Analysis of the viability of the predator mite Blattisocius tarsalis as a biological control agent for this moth was carried out. A study of the temperature effect showed B. tarsalis maintains predatory capacity in the range of 10–27 °C. Though predatory activity increases with temperature, no differences in mortality rates were observed between 10 and 20 °C (33.52 ± 2.44 and 40.14 ± 3.54% efficacy rate, respectively), nor between 25 and 27 °C (59.26 ± 4.59 and 75.19 ± 4.64% efficacy rate, respectively). Under microcosm conditions, at low pest infestation (10 eggs), B. tarsalis achieved the highest mortality of eggs at a density of 5 mites, with an efficacy rate of 91.67 ± 8.33%. At high infestation levels (50 eggs), maximum mortality was achieved with a density of 10 mites and efficacy of 98.52 ± 1.48%. The choice-assay showed no preference of B. tarsalis between T. solanivora and Phthorimaea operculella, suggesting this mite could be useful in mixed infestations of potato moths. The results show B. tarsalis is a very good candidate as a control agent in storage conditions and even in mixed infestations of T. solanivora and P. operculella.

The Persea mite, Oligonychus perseae, was identified for the first time in the Canary Islands (Spain) in 2006 becoming a major pest in avocado crops. This study analyses seasonal trends of Persea mite and phytoseiid predatory mites. The study aims to gain a better understanding of pest-predator dynamics and assess which predators have potential as biological control agents. In addition, predatory mites present in resident wild ground cover were studied with a view to promoting biological control. Results showed that Persea mite was present year-round with one or two peaks from April to July. The incidence of O. perseae varied depending on the avocado production area, but in all of them, it exceeded the density of 100 mites/leaf, established as the action threshold. Phytoseiids were more abundant on the trees in late winter, spring and early summer. Euseius stipulatus, Neoseiulus californicus and E. scutalis represented almost 96.5% of phytoseiids collected in commercial avocado orchards. They were also the most abundant species in the untreated study site. Resident wild ground cover associated with commercial avocado orchards was composed of 45 plant species belonging to 22 families, with Urticaceae and Asteraceae harbouring the highest richness in phytoseiid species.